Electro-magnetically shielded connector

ABSTRACT

An electro-magnetically shielded connector comprises a connector body including at least two housings; an electrically conductive layer formed on a surface of one of the two housings in such a manner that the electrically conductive layer covers a surface of the one housing, and when the two housings are combined with each other, at least a part of the electrically conductive layer on an inner surface of the one housing is exposed; and main electrically connecting device for electrically connecting the electrically conductive layer of the connector body and a shield of a shielded cable to seal an inside of the connector body.

This is a divisional of Ser. No. 439,788, filed May 12, 1995 now U.S.Pat. No. 5,501,615 issued Mar. 26, 1996, which is a divisional of Ser.No. 249,199, filed May 26, 1994, now U.S. Pat. No. 5,460,544 issued Oct.24, 1995.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a shielded connector having anelectro-magnetic shield function and a water-proof function.

2. Related Art

FIG. 8 shows a shielded connector which is disclosed, for instance, byUnexamined Japanese Utility Patent Application No. 127083/1988.

The shielded connector 4 comprises: a connector housing 41 of syntheticresin; a metal shield 42 formed on the inner surface of the connectorhousing 41; a shielded cable 46 from which sheathed wires 46 areprotruded, the wires 46 being connected to press-connecting terminals 44in the terminal receiving section 43 of the connector housing; and acrimping part 48 which is integral with the metal shield 42, beingconnected to the braided shield 47 of the shielded cable 46.

When the press-connecting terminals 44 connected to the sheathed wires45 of the shielded cable 46 are engaged with the connector housing 41,noises generated by the latter 41 are magnetically shielded by the metalshield 42, and grounded through the braided shield 47 and a drain line49 provided inside the former.

FIG. 9 shows the water-proof structure of a conventional shieldedconnector disclosed by Japanese Patent Application (OPI) No.182071/1991. In order to prevent the entrance of water into theconnector through the braided shields 50 of shielded wires 52, theshield connector has a rubber member 55 which is formed on it by moldingin such a manner that it covers the shielded connector from the bases ofthe shielded wires 52 to the ends of braided wires 51.

However, the above-described water-proofing structure is disadvantageousin the following points: Since the braided wires 51 are covered with therubber member 55, they are difficult to bend, and therefore theengagement and disengagement of the terminals 56 are rather troublesome.In addition, the formation of the rubber member 55 by molding takes alot of time and labor.

In the above-described shielded connector 40 shown in FIG. 8, theshielded cable 46 is fixed to the metal shield 42 with the crimping part48 which is integral with the metal shield 42. And no water-proofingmeans is provided for the junction between the shielded cable 46 and theconnector housing 41, and therefore water may go into the connectorthrough the junction.

In order to ground the noises generated by the connector housing 41;that is, in order to obtain a shielding function, the metal shield 42 isfitted in the connector housing 41. Hence, the shielded connector isrelatively large in the number of components, and the manufacturing ofthe components and the assembling of them take a lot of time and labor.

SUMMARY OF THE INVENTION

In view of the foregoing, an object of this invention is to provide anelectro-magnetically shielded connector in which, at the junctionbetween an connector housing and a shielded cable, is satisfactory inelectrical conduction and has a sufficiently high shielding function,and which is positively water-proofed, and in which the number ofcomponents is smaller than in the prior art, and the components can bemanufactured and assembled more readily. The invention has beendeveloped to eliminate the above-described difficulties and problems.That is, another object of the invention is to provide anelectro-magnetically shielded connector which is light and small, andwhich is low in manufacturing cost, and which is sufficientlywater-proofed and dust-proofed.

The invention is to eliminate the above-described difficulties andproblems. That is, another object of the invention is to provide anelectro-magnetically shield connector which is simple in the control ofmanufacturing tolerances, thus being high in yield, and which is low inmanufacturing cost, and is sufficiently water-proofed and dust-proofed.

An aspect of the present invention is to provide a shielded connectorcomprising:

a metal shield is formed in a connector housing of synthetic resin bymolding,

a water-proof plug is mounted on a shielded cable connected to anelectrical terminal, which is inserted into the connector housing, insuch a manner that the water-proof plug is in close contact with theshield of a shielded cable connected, and

the water-proof plug is provided with electrically conducting means withrespect to the metal shield.

Another aspect of the present invention is to provide anelectro-magnetically shielded connector comprising:

a connector body into which a shielded cable is inserted through therear end opening, the connector body comprises at least two housings,

an electrically conductive layer which is relatively thin is formed onthe surface of one of the two housings in such a manner that theelectrically conductive layer covers the outer surface of the onehousing and a part of the inner surface of the one housing, and, whenthe two housings are combined with each other, at least a part of theelectrically conductive layer on the inner surface of the one housing isexposed, and

the inside of the connector body is sealed with an electricallyconductive elastic member in such a manner that the shield of theshielded cable and the electrically conductive layer exposed inside theconnector body are electrically connected to each other being pressed bythe electrically conductive elastic member.

Another aspect of the present invention is to provide anelectro-magnetically shielded connector comprising: a female connectorincluding a first shielding electrical conductor a portion of which isexposed in at least a part of the outer surface of the female connector;and a male connector including a second shielding electrical conductor aportion of which is exposed in at least a part of the inner surface ofthe male connector, the first and second shielding electrical conductorsthus exposed being electrically connected to each other, the diameter ofthe portion of the second shielding electrical conductor is larger thanthe diameter of the portion of the first shielding electrical conductor,and an electrically conductive elastic member is interposed between theexposed portions of the first and second shielding electricalconductors, thus electrically connecting the first and second electricalconductors to each other through the exposed portions.

In the shielded connector, the metal shield is formed in the connectorhousing of synthetic resin by molding, and the electrically conductingmeans is provided for the water-proof plug mounted on the shieldedcable, so that the water-proof plug is closely engaged with the metalshield. Hence, by inserting the terminal unit connected to the shieldedcable into the connector housing, the metal shield of the connectorhousing and the braided shield of the shielded cable are electricallyconnected through the water-proof plug to each other, thus providing ashielding function, and at the same time, the shielded connector iswater-proofed.

In the electro-magnetically shielded connector, the electricallyconductive layer which is relatively thin is formed on the surface ofone of the two housings in such a manner that the electricallyconductive layer covers the outer surface and a part of the innersurface of the one housing, and, when the two housings are combined witheach other, at least a part of the electrically conductive layer on theinner surface of the one housing is exposed. And when the shielded cableis inserted into the connector body through the rear end opening and theinside of the connector body is sealed with the electrically conductiveelastic member, the shield of the shielded cable and the electricallyconductive layer exposed inside the connector body are electricallyconnected to each other being pressed by the electrically conductiveelastic member, thus forming a shielding wall which is relatively light.At the same time, the shielded connector is water-proofed with theelectrically conductive elastic member sealingly engaged with it.

The diameter of the exposed portion of the shielding electricalconductor of the male connector is larger than that of the exposedportion of the shielding electrical conductor of the female connector.Hence, when the male connector is engaged with the female connector, agap is formed between the exposed portions of the shielding conductorsof the male and female connectors. The gap is filled with theelectrically conductive elastic member, so that the exposed portions ofthe shielding electrical conductors are electrically connected throughthe electrically conductive elastic member to each other, thus forming ashielding wall. The electrically conductive elastic member is adjustablein volume. Hence, even if the gap is variable in dimension, it can besufficiently filled with the electrically conductive elastic member.Furthermore, the electrically conductive elastic member, being heldcompressed in the gap, prevents the entrance of water into the shieldedconnector.

BRIEF DESCRIPTION OF THE DRAWINGS)

FIG. 1 is an exploded sectional view showing a shielded connector, whichconstitutes a first embodiment of this invention;

FIG. 2 is a longitudinal sectional view showing the shielded connectorwhich is obtained by combining a connector housing with a terminal unitbearing a shielded cable;

FIG. 3 is an exploded perspective view showing the shielded connectorwhich is to be engaged with a mating connector;

FIG. 4 is a longitudinal sectional view showing the shielded connectorwhich has been engaged with the mating connector;

FIG. 5 is an exploded sectional view showing a shielded connector, whichconstitutes a second embodiment of the invention;

FIG. 6 is a longitudinal sectional view of the shielded connector shownin FIG. 5;

FIG. 7 is a longitudinal sectional view showing the shielded connectorshown in FIG. 5 which has been engaged with a mating connector;

FIG. 8 is a perspective view of a conventional shielded connector;

FIG. 9 is a front view, with parts cut away, showing the conventionalshielded connector;

FIG. 10 is a longitudinal sectional view showing an electro-magneticallyshielded connector, which constitutes a third embodiment of theinvention;

FIG. 11(a) is a longitudinal sectional view of an inner housing whichforms the shielded connector shown in FIG. 10;

FIG. 11(b) is a longitudinal sectional view of a connector body whichcomprises the inner housing and an outer housing engaged with theformer;

FIG. 11(c) is also a longitudinal sectional view showing a terminal unitwhich is engaged with the connector body;

FIG. 12 is a longitudinal sectional view showing an electro-magneticallyshielded connector, which constitutes a fourth embodiment of theinvention;

FIG. 13 is a longitudinal sectional view of a male connector forming theshielded connector shown in FIG. 12;

FIG. 14(a) is a longitudinal sectional view of inner and outer housingsforming the female connector of a fifth embodiment of the presentinvention;

FIG. 14(b) is a longitudinal sectional view of a terminal unit to beengaged with the female connector; and FIG. 14(c) is a longitudinalsectional view showing the female connector engaged with the terminalunit;

FIG. 15(a) is a longitudinal sectional view showing a female connectorand a male connector which are engaged with each other to form theshielded connector of fourth embodiment of the present invention; and

FIG. 15(b) is a sectional view for a description of the dimensions ofshielding conductive parts in the shielded connector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment

A first embodiment of this invention will be described with reference toFIGS. 1 through 4.

As shown in those figures, a shielded connector 1, which constitutes thefirst embodiment of the invention, includes: a connector housing 2 whichis substantially cylindrical and made of synthetic resin; a metal shield3 which is substantially cylindrical and formed inside the connectorhousing 2 by molding in such a manner that it is integral with thelatter 2; a shielded cable 6 connected to an electrical terminal 5 whichis inserted into an receiving chamber circular in section which isdefined by the connector housing 2; a locking member of synthetic resinwhich is engaged with the electrical terminal 5; a connecting member 10which is annular and made of electrically conductive metal; and awater-proof plug 13 which is substantially tubular and elastic. Theconnecting member 10 has one end portion which is press-connected ontothe braided shield 8 of the shielded cable 6, and the other end portionincluding a contact portion 9 which is brought into contact with theinner surface of the rear of the metal shield 3. The water-proof plug 13is fixedly mounted on the shielded cable 6 in such a manner as to coverthe latter from the exposed braided shield 8 till the sheath 11. Thewater-proof plug 13 is adapted to close the rear opening 12 of thereceiving chamber 4. The plug 13 is held pushed against the innersurface of the contact portion 9 of the connecting member 10 bycaulking.

The front end portion of the connector housing 2 is formed into acylindrical portion 14 relatively small in diameter. The cylindricalportion 14 has an inserting hole 15 into which the mating terminal ofthe aforementioned electrical terminal 5 is inserted. A locking-memberinserting hole 16 is formed in the cylinder at the middle in such amanner that it is communicated with the receiving chamber 4. Thereceiving chamber 4 is opened in the rear end portion of the connectorhousing 2; that is, the connector housing 2 has a hollow engagingportion 17 at the rear end which is larger in diameter than thereceiving chamber 4.

The hollow engaging portion 17 has a receiving step 17a, which is usedas follows: When the electrical terminal 5 connected to the shieldedcable 6 is inserted into the receiving chamber 4 of the connectorhousing 2, the step 17a allows the water-proof plug 13 to be closelyfitted therein, so that the junction of the connector housing and theelectrical terminal is water-proofed and the further insertion of theelectrical terminal 5 is prevented.

The metal shield 3 is buried in the connector housing 2 in conformanceto the configuration of the latter 2. More specifically, the metalshield is extended from the front end of the cylindrical portion 14towards the hollow engaging portion 17. The rear end portion of themetal shield 3 is positioned before the hollow engaging portion 17: thatis, a contact portion 18 which is provided on the inner surface of thereceiving chamber 4 in correspondence to the contact portion 9 of theconnecting member 10, is annularly exposed before the hollow engagingportion 17.

The contact portion 18 has a tapered portion 19 at the rear end which islarger in diameter towards the hollow engaging portion 17. With thetapered portion 19, the connecting member 10 can be smoothly guided andmoved.

The connecting member 10 comprises: an annular press-contacting portion20 which is relatively small in diameter and is mounted on the braidedshield 8 of the shielded cable 6; a sloped (tapered) portion 21 which isextended backwardly from the press-contacting portion 20 in such amanner that its diameter is larger towards the rear end; and theaforementioned annular contact portion 9 which is extended backwardlyfrom the sloped portion 21.

The water-proof plug 13 is pressed against the inner surface of thecontact porion 9, so that the latter 9 is urged outwardly at all times;that is, it is strongly pushed against the contact portion 18 of themetal shield 3.

In the water-proof plug 13, the inner cylindrical surface has a step 22,and the outer cylindrical surface also has a step 23 which is tapered.The water-proof plug 13 is mounted on the shielded cable 6 with theinner step 22 abutted against the end of the sheath 11 of the shieldedcable 6 and with the outer step 23 abutted against the end of thecontact portion 9 of the connecting member 10.

The water-proof plug 13 includes a large-diameter portion 24 which has alip 24a on its outer cylindrical surface. The large-diameter portion 14is brought into close contact with the hollow engaging portion 17 of theaccommodating chamber 4, to prevent the entrance of water into theconnector housing 2.

The close contact of the water-proof plug 13 is achieved by insertingthe terminal unit 5 connected to the shielded cable 6 into the receivingchamber 4. In this operation, the contact portion 9 of the connectingmember 10 is brought into slide contact with the contact portion 18 ofthe metal shield 3, so that the braided shield 8 is connected throughthe connecting member 10 to the metal shield.

The electrical terminal 5 is pulled out of the connector housing asfollows: That is, first the locking member 7 is removed from the lockingmember inserting hole 16 of the connector housing 2, and then theshielded cable 6 is pulled out. Even if, in this case, the sheathed wire25 connected to the electrical terminal 5 is short, it will not affectthe operation, because the connecting member 10 is separated from thecontact porion 18 of the metal shield 3. The above description isapplicable to the case where a plurality of sheathed wires (25) areprotruded from the shielded cable 6.

The electrical terminal 5 comprises a pin connecting portion 26 and awire connecting portion 27, and an annular recess 28 between them. Thelocking member 7 is engaged with the annular recess 28 of the electricalterminal 5, so that the latter 5 is prevented from coming off theconnector housing 2.

When, as shown in FIGS. 3 and 4, the shielded connector 1 is engagedwith a mating connector 30, the terminal unit 5 is connected with a pinterminal 31. The connector 30 has a housing 32 including an engagingportion 33. In the connector 30, the pin terminal 31 inserted into thecylindrical portion 14 of the connector housing 2 is protruded in theengaging portion 33 of the housing 32. After the electrical terminal 5is connected with the pin terminal 31, the pawl 35 of a rocking arm 34is locked to an engaging protrusion 36 formed on the shieldedconnector 1. A metal shield 37 is buried in the housing 32 by molding.An annular packing 38 is set in the engaging portion 33, which isengaged with the cylindrical portion 14 of the connector housing 2 whenthe shielded connector 1 is engaged with the mating connector 30, sothat, after the connection of those connectors, the entrance of waterthereinto is prevented.

Second Embodiment

FIGS. 5 through 7 show a second embodiment of the invention.

In the above-described first embodiment, the connecting member 10 ofmetal, which is brought into close contact with the braided shield 8 ofthe shielded cable 6, is fitted on the water-proof plug 13 mounted onthe shielded cable 6. Therefore, in the first embodiment, the shieldingeffect is obtained as follows: With the connecting member 10electrically connected to the braided shield 8, the electrical terminal5 connected to the shielded cable 6 is inserted into the connectorhousing 2 through the opening 12 until the connecting member 10 iselectrically connected to the metal shield 3. At the same time, theentrance of water through the shielded cable 6 is prevented by thewater-proof plug 13 which is elastic. Furthermore, the contact portion 9of the connecting member 10 is kept pressed against the metal shield 3,being urged by the elastic force of the water-proof plug 13.

On the other hand, in the second embodiment, a waterproof plug 13 madeof electrically conductive rubber is mounted on the shielded cable 6 insuch a manner that, it covers the latter 6 from the braided shield 8 tothe sheath 11. Furthermore, in the second embodiment, unlike the firstembodiment, the connecting member 10 of metal is not employed, andinstead, the rear end portion of a metal shield 3 buried in theconnector housing 3 by molding is folded and exposed in the receivingchamber 4; that is, a folded portion 3a is formed which is brought intoclose contact with the water-proof plug 13 when the electrical terminal5 is engaged with the connector housing 2. That is, in the secondembodiment, the metal shield 3 of the connector housing 2 iselectrically connected through the water-proof plug 13 to the braidedshield 8 of the shielded cable 6, to form a shielding wall.

Hence, in the second embodiment, the number of components is reduced,and the components can be manufactured and assembled with ease. Inaddition, the second embodiment has the same effects and functions asthe first embodiment.

As was described above, in the first and second embodiments of theinvention, when the shielded cable is connected to the connectorhousing, the water-proof plug having the electrically conducting meansis closely fitted in the hollow engaging portion of the connectorhousing in which the metal shield is buried by molding. Hence, theshielded connector is satisfactory in electrical conduction at thejunction between an connector housing and a shielded cable, thus havinga sufficiently high shielding function, and is positively water-proofed.Furthermore, the number of components is smaller than in the prior art,and the components can be manufactured and assembled more readily.

However, the first and second embodiments of the invention are limitedby the following points: A metal mold for burying the metal shield inthe connector housing is expensive. The metal shield itself isrelatively heavy. Hence, it is difficult to reduce the weight of theshielded connector.

In addition, it is rather difficult to miniaturize the shieldedconnector.

In order to eliminate the above-described difficulties accompanying thefirst and second embodiments, a third embodiment of the invention hasbeen developed.

Third Embodiment

The third embodiment will be described with reference to FIGS. 10 and11.

FIG. 10 is a sectional view showing an electro-magnetically shieldedconnector, which constitutes the third embodiment of the invention.

FIGS. 11(a) to (c) are sectional views showing components of theshielded connector.

As shown in FIG. 10, the shielded connector 101 comprises: a connectorbody 102; and a terminal unit 105 fitted in the connector body 102.

The structure and the assembling of the connector body 102 will bedescribed with reference to FIGS. 11(a) and (b). The connector body 102comprises an inner housing 121 of resin, and an outer housing 122 ofresin. The outer surface of the inner housing 121 is partially coveredwith a thin conductive layer 123.

More specifically, the inner housing 121 is substantially in the form ofa hollow cylinder which is made of insulating synthetic resin or thelike. The inner housing 121 is opened wide at the rear end; that is, therear end portion of the inner housing is larger in inside diameter thanthe other portion. A locking hole 125 is formed in the inner housing 121slightly before the middle.

The thin conductive layer 123 is spread over the outer surface of theinner housing 121 substantially from the middle towards the rear end.The conductive layer 123 thus spread is folded at the rear end of theinner housing 121 and extended over the rear end portion of the innersurface. That is, the same conductive layer 123 is laid over thesubstantially half of the outer surface and the rear end portion of theinner surface.

In other words, the inner and outer surfaces of the inner housing 121are selectively covered with the conductive layer 123.

The thin conductive layer 123 is formed on the predetermined portions ofthe inner and outer surfaces of the inner housing 121 by a variety ofplating methods such as an electroless plating method, or other methodsof impregnating and vacuum-depositing electrically conductive material,and applying electrically conductive paint.

The outer housing 122 is formed on the inner housing 121 in such amanner that the front end portion 123A of the conductive layer 123 onthe outer surface of the inner housing 121 is exposed (hereinafterreferred to as "an exposed portion 123A", when applicable), and theconductive layer 123 on the inner surface of the inner housing 121 isexposed as indicated at 123B (hereinafter referred to as "an exposedportion 123B", when applicable) (the remaining portions being covered bythe outer housing 122). Thus, the connector body 102 has been formed.

Now, the structure of the terminal unit 5 will be described withreference to the part (c) of FIG. 11.

The terminal unit 5 comprises: a terminal 116 bearing the conductor 7 ofa shielded cable 106; and an electrically conductive rubber plug 109.The conductive rubber plug 109 has a contact portion 113 which isbrought into contact with the braided shield 108 of the shielded cable106. The conductive rubber plug 109 is mounted on the shielded cable 116in such a manner as to cover the latter 116.

The conductive rubber plug 109 has a contact portion 114 on the outersurface of its rear half. The contact portion 114 is electricallyconnected to the braided shield 108.

The engagement of the electrical terminal 5 to the connector body 102will be described with reference to FIG. 10.

The terminal unit 105 is inserted into the connector body 102 throughthe rear end opening 124 until the terminal 116 abuts against the frontannular bottom of the inner housing 121. Under this condition, a stopper126 is inserted into the locking hole 125 of the connector body 102, toposition the electrical terminal 5 in place. In this operation, theelectrically conductive rubber plug 126 is sufficiently pushed in theforward direction so that it seals the connector body around the rearend opening, thus isolating the inside of the connector body 102 fromthe outside; that is, preventing the entrance of water and dust into theconnector body. In addition, an outer plug 112 such as a rubber bushingmay be employed as shown in FIG. 10.

The contact portion 114 of the conductive rubber plug 109 pushes theexposed portion 123B of the conductive layer 123 strongly, so that thecontact portion 114 is electrically connected to the exposed portion123B. As a result, a shielding wall is formed which is extended from thebraided shield 108 through the electrically conductive rubber plug 109to the exposed portion 123A of the conductive layer 123.

As was described above, in the electro-magnetically shielded connectorof the third embodiment of the present invention, the conductive layer123, unlike the metal shield formed by blanking a metal plate, is in theform of a thin film. Hence, the shielded connector is lighter andsmaller. Furthermore, the shield of the shielded cable can be connectedwithout the use of a connecting member such as the one in the shieldedconnector. Therefore, the shielded connector of the invention is smallerin the number of components, which reduces the manufacturing cost asmuch.

The shielded connector is tightly sealed with the electricallyconductive rubber plug and the bushing; that is, it is sufficientlywater-proofed and dust-proofed.

As was described above, in the electro-magnetically shielded connectorof the third embodiment of the present invention, the connector body ismade up of at least two housings, and the electrically conductive layerwhich is thin is formed over the outer surface and the inner surface ofone of the two housings in such a manner that, when the two housings arecombined with each other, a part of the conductive layer is exposed overthe inner surface. When the connector body is sealed with theelectrically conductive elastic member, the shield of the shielded cableis pressed against the exposed part of the conductive layer. Hence, theshielded connector is smaller in the number of components, and isreduced in manufacturing cost as well as in weight and in size.Furthermore, the shielded connector is positively water-proofed anddust-proofed; that is, it is prevented from being erroneously operatedor from being shortened in service life by the entrance of rust or dustthereinto.

Fourth Embodiment

FIGS. 15(a) and (b) shows a shielded connector 101, which constitutes afourth embodiment of the invention. More specifically, the part (a) ofFIG. 15 is a vertical sectional view of the shielded connector with maleand female connectors engaged with each other, and the part (b) of FIG.15 is a sectional view for a description of the dimensions of shieldingelectrical conductors in the shielded connector.

As shown in those figures, the shielded connector 101 comprises: thefemale connector 102 employed in the above-described third embodiment;and a male connector 103. The female connector 102 comprises: an innerhousing 121 on which an electrically conductive layer 123 is formed byplating; an outer housing 122, and a terminal unit 105 which bears ashielded cable 123 and has an electrically conductive elastic member 109through which the conductive layer 123 is electrically connected to thebraided shield 108 of the shielded cable. On the other hand, the maleconnector 103 comprises: an outer housing 103A on which an electricallyconductive layer 131 is formed by plating; and an inner housing 103B.

The conductive layer 123 of the female connector 102 is a shieldingconductive layer, and it includes an exposed portion 123A on the outersurface of the inner housing. The diameter of the exposed portion 123Ais Rs. Similarly, the conductive layer 131 of the male connector 103includes an exposed portion 131A on the inner surface of the outerhousing 103A. The diameter of the exposed portion 123A is slightlylarger than Rs.

When the female connector 102 is engaged with the male connector 103,the exposed portion 123A is brought into contact with the contact region131B of the exposed portion 131A; that is, the shielding conductivelayers of the male and female connectors are electrically connected witheach other.

As a result, the conductive layer 132 is electrically connected to thebraided shield 8 of the shielded cable, thus forming anelectro-magnetically shielding wall.

In the fourth embodiment of the invention, the exposed portion 123A ofthe conductive layer 123 of the female connector 102 is brought directlyinto contact with the exposed portion 131A of the conductive layer 131of the male connector 103. Hence, the shielded connector suffers fromthe following difficulties: That is, the control of manufacturingtolerances is rather troublesome, as a result of which the yield islowered, and the manufacturing cost is increased.

In addition, it is rather difficult to realize the water- proof anddust-proof of the shielded connector.

In order to eliminate the above-described difficulties accompanying thefourth embodiment, a third embodiment of the invention has beendeveloped.

Fifth Embodiment

A fifth embodiment of the invention will be described with reference toFIGS. 12, 13 and 14.

FIG. 12 is a longitudinal sectional view of an electro-magneticallyshielded connector 201, which constitutes the fifth embodiment of theinvention. FIG. 13 is a longitudinal sectional view showing a maleconnector 203 in the shielded connector. The parts (a) through (c) ofFIG. 14 are also longitudinal sectional views showing a female connector202 in the shielded connector.

The shielded connector 201, the fifth embodiment of the invention,comprises: a female connector 202; and a male connector 203.

First, the structure of the male connector 203 will be described withreference to FIG. 13. The male connector comprises: an outer housing203A of resin; and an inner housing 203B of resin. An electricallyconductive layer 231, which is thin, is formed on the inner surface ofthe outer housing 203A.

More specifically, the outer housing 203A is made of insulatingsynthetic resin and is substantially in the form of a cup opened at therear end.

The conductive layer 231 is formed over the inner surface of the outerhousing 203A as was described above, and it is exposed, as indicated at231A, at the rear end of the outer housing when the latter is engagedwith the inner housing (hereinafter referred to as "an exposed portion231A", when applicable). The diameter of the exposed portion 231A is Rm,which is larger than the diameter Rs of the exposed portion 223A(described later) of the conductive layer 223 of the female connector202.

The conductive layer 231 is formed by a variety of plating methods suchas an electroless plating method, or other methods, impregnating andvacuum-depositing electrically conductive material, and applyingelectrically conductive paint.

The inner housing 203B is formed by using a resin which is lower inmelting point than the resin of the outer housing 203A, in such a manneras to cover substantially the front half of the inner surface of theouter housing 203A on which the conductive layer 231 has been formed.

More specifically, the inner housing 203B thus formed covers theconductive layer 231 except the aforementioned exposed portion 231A atthe rear end of the outer housing 203. Thus, the male connector 203 hasbeen fabricated.

Now, the structure of the female connector 202 will be described withreference to FIGS. 14.

The female connector 202 comprises: an inner housing 221 and an outerhousing 222 as shown in the part (a) of FIG. 14; and a terminal unit 205as shown in the part (b) of FIG. 14.

An electrically conductive layer 223 is formed on the outer surface ofthe inner housing 221, and then the outer housing 222 is formed on theconductive layer 223, thus providing exposed portions 223A and 223B asshown in the part (a) of FIG. 14. The exposed portion 223A has adiameter of Rs.

The terminal unit 205 is adapted to bear the conductor 207 of a shieldedcable 206, and has an electrically conductive elastic member 203 whichis brought into contact with the braided shield 8 of the shielded cable206 in such a manner that it covers the latter 206.

The above-described components are assembled into the female connector202 as shown in the part (c) of FIG. 14.

As the end portion of the terminal unit 205 is engaged with the innerhousing 221, the electrically conductive elastic member 209 stronglypresses the exposed portion 223B of the conductive layer 223, thus beingelectrically connected to the latter. As a result, inside the femaleconnector 202, a shielding wall is formed which is extended continuouslyfrom the braided shield 208 through the elastic member 209 to theexposed portion 223A of the conductive layer 223.

When the female connector 202 is engaged with the male connector 203, asshown in FIG. 12 the end portion of the female connector 202; i.e., theinner housing 221 of the latter is fitted in the inner housing 203B ofthe male connector 203. In this case, at the rear end portion of themale connector, a gap is formed between the exposed portion 231A (Rm indiameter) of the conductive layer 231 and the exposed portion 223A (Rsin diameter) of the conductive layer 223.

An electrically conductive elastic member 32 is inserted into the gapthus formed in such a manner that it is held sufficiently compressedtherein. As a result, the exposed portion 231A is electrically connectedthrough the electrically conductive elastic member 32 to the exposedportion 223A; that is, the conductive layer 231 is electricallyconnected to the conductive layer 223.

Thus, a shielding wall has been formed which is extended from thebraided shield 208 of the shielded cable 206 through the electricallyconductive elastic member 209, the conductive layer 223 and theelectrically conductive elastic member 232 to the conductive layer 231.

The electrically conductive elastic member 32, which is heldsufficiently compressed in the aforementioned gap, isolates the insideof the male connector 203 from the outside, thus preventing the entranceof water or dust into the shielded connector.

That is, by inserting the electrically conductive elastic member 32 intothe gap in such a manner that it is held compressed therein, not onlythe shielding wall of the shielded connector is formed, but also theshielded connector is prevented from the entrance of water or dust.

The shielded connector can be further improved in water- proof and indust-proof by sealing the rear end of the male connector 203 with anouter plug 233 such as a rubber bushing. After the male and femaleconnectors have been combined as described above, a turning arm 234provided on the male connector 203 is turned until its pawl 235 isengaged with a protrusion formed on the female connector 202.

As was described above, in the electro-magnetically shielded connector,the fifth embodiment of the invention, the diameter of the exposedportion of the electrically conductive layer of the male connector islarger than that of the exposed portion of the electrically conductivelayer of the female connector. Hence, in manufacturing the components,the tolerances on them may not be so severe, as a result of which theyield is increased as much, and accordingly the manufacturing cost isdecreased.

After the male and female connectors are engaged with each other, thegap formed between the exposed portions of the electrically conductivelayers of the male and female connectors is filled with the electricallyconductive elastic member, so that the exposed portions are electricallyconnected to each other through the electrically conductive elasticmember; that is, the conductive layers of the male and female connectorsare electrically connected to the braided shield of the shielded cable,thus forming the shielding wall. The electrically conductive elasticmember can be adjust in volume. Hence, even if the gap is variable indimension, it can be sufficiently filled with the electricallyconductive elastic member. Furthermore, the electrically conductiveelastic member held compressed in the gap prevents the entrance of wateror dust into the shielded connector. That is, the shielded connector isfree from the difficulties that because of the formation of rust or thepresence of dust, the shielded connector is operated erroneously or itis shortened in service life.

What is claimed is:
 1. An electro-magnetically shielded connectorcomprising:a first connector body including at least two housings; anelectrically conductive layer formed on a surface of one of the twohousings in such a manner that the electrically conductive layer coversa surface of the one housing, and when the two housings are combinedwith each other, at least a part of the electrically conductive layer onan outer surface of the one housing is exposed; and main electricallyconnecting means for electrically connecting the electrically conductivelayer of the first connector body and a shield of a shielded cable toseal an inside of the first connector body.
 2. An electro-magneticallyshielded connector as claimed in claim 1, wherein the main electricallyconnecting means includes an electrically conductive elastic member. 3.An electro-magnetically shielded connector as claimed in claim 1,wherein the housings are made of different resins, respectively, and oneresin has a melting temperature which is lower than the other resin. 4.An electro-magnetically shielded connector as recited in claim 1,wherein said first connector body comprises a female connector;saidshielded connector further comprising a male connector including:atleast two housings; an electrically conductive layer formed on an innersurface of one of the two housings in such a manner that theelectrically conductive layer covers a surface of the one housing, andwhen the two housings are combined with each other, at least a part ofthe electrically conductive layer on the inner surface of the onehousing is exposed; wherein when the male connector and the femaleconnector are assembled, the electrically conductive layer of the maleconnector and the electrically conductive layer of the female connectorare directly in contact with each other.
 5. An electro-magneticallyshielded connector as claimed in claim 4 wherein the male connector hasa insertion hole for receiving the female connector therein, and theinsertion hole having a diameter which is larger than a diameter of thefemale connector.
 6. An electro-magnetically shielded connector asclaimed in claim 5, further comprising:auxiliary electrically connectingmeans for electrically connecting the electrical conductive layer of thefemale connector and the electrical conductive layer of the maleconnector to seal a gap between the female connector and the maleconnector.
 7. An electro-magnetically shielded connector as claimed inclaim 6, wherein an auxiliary electrically connecting means includes anelectrically conductive elastic member.
 8. An electro-magneticallyshielded connector as claimed in claim 4, further comprising:fixingmeans for fixing the female connector and the male connector, the fixingmeans being provided with the male connector and the female connector.9. An electro-magnetically shielded connector as claimed in claim 8,wherein the fixing means includes a rotating arm mounted on an outerperiphery of the male connector and an engaging claw mounted on an outerperiphery of the female connector.
 10. An electro-magnetically shieldedconnector as claimed in claim 5, wherein the main electricallyconnecting means includes an electrically conductive elastic member.